A mono-aziridinyl group containing curing agent is synthesized from the addition reaction of aziridine with isophorone diisocyanate (IPDI) in equal molar ratio. It is resulting in a compound consists of isocyanate and aziridinyl groups. This newly prepared compound is purified and characterized by the spectrophotometric methods. This new compound is introduced into an aqueous-based amino- terminated PU dispersion and resulting a self-curable aqueous-based PU dispersion. The isocyanate and the aziridinyl groups of the compound react with the terminal amino and carboxylic groups of aqueous-based polyurethane within PU micelles and on the drying process, respectively. This compound owns two separated reactive functional groups serves as a new curing agent for the carboxylic group containing aqueous-based polyurethane. The performance properties of this cured PU with this new curing agent are investigated.